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February 24, 2004 12:00 am
Let's compare J.J. Hardy and Bobby Crosby:
Player Age EqBA/EqOBP/EqSLG
Hardy 20 .240/.316/.380
Crosby 23 .273/.356/.490
Adjusted for park and league context, Crosby's numbers were much, much better. How to balance that against the age differential? I think the question becomes: How likely is it that Hardy will post a line of .273/.356/.490 or equivalent by the time that he's 23? It's possible, certainly, and it's also possible that he'll post a line even better than that. But I don't think that it's *probable*. That's a lot of improvement to make. PECOTA would put the possibility at somewhere around 25%, I'd think, and I think that's enough to render Crosby the stronger prospect.
Baseball Prospectus Top 40 Prospects Roundtables:
2003 Part II
2003 Part I
October 12, 2000 12:00 am
\nMathematically, leverage is based on the win expectancy work done by Keith Woolner in BP 2005, and is defined as the change in the probability of winning the game from scoring (or allowing) one additional run in the current game situation divided by the change in probability from scoring\n(or allowing) one run at the start of the game.';
xxxpxxxxx1160184488_18 = 'Adjusted Pitcher Wins. Thorn and Palmers method for calculating a starters value in wins. Included for comparison with SNVA. APW values here calculated using runs instead of earned runs.';
xxxpxxxxx1160184488_19 = 'Support Neutral Lineup-adjusted Value Added (SNVA adjusted for the MLVr of batters faced) per game pitched.';
xxxpxxxxx1160184488_20 = 'The number of double play opportunities (defined as less than two outs with runner(s) on first, first and second, or first second and third).';
xxxpxxxxx1160184488_21 = 'The percentage of double play opportunities turned into actual double plays by a pitcher or hitter.';
xxxpxxxxx1160184488_22 = 'Winning percentage. For teams, Win% is determined by dividing wins by games played. For pitchers, Win% is determined by dividing wins by total decisions. ';
xxxpxxxxx1160184488_23 = 'Expected winning percentage for the pitcher, based on how often\na pitcher with the same innings pitched and runs allowed in each individual\ngame earned a win or loss historically in the modern era (1972-present).';
xxxpxxxxx1160184488_24 = 'Attrition Rate is the percent chance that a hitters plate appearances or a pitchers opposing batters faced will decrease by at least 50% relative to his Baseline playing time forecast. Although it is generally a good indicator of the risk of injury, Attrition Rate will also capture seasons in which his playing time decreases due to poor performance or managerial decisions. ';
xxxpxxxxx1160184488_25 = 'Batting average (hitters) or batting average allowed (pitchers).';
xxxpxxxxx1160184488_26 = 'Average number of pitches per start.';
xxxpxxxxx1160184488_27 = 'Average Pitcher Abuse Points per game started.';
xxxpxxxxx1160184488_28 = 'Singles or singles allowed.';
xxxpxxxxx1160184488_29 = 'Batting average; hits divided by at-bats.';
xxxpxxxxx1160184488_30 = 'Percentage of pitches thrown for balls.';
xxxpxxxxx1160184488_31 = 'The Baseline forecast, although it does not appear here, is a crucial intermediate step in creating a players forecast. The Baseline developed based on the players previous three seasons of performance. Both major league and (translated) minor league performances are considered.
The Baseline forecast is also significant in that it attempts to remove luck from a forecast line. For example, a player who hit .310, but with a poor batting eye and unimpressive speed indicators, is probably not really a .310 hitter. Its more likely that hes a .290 hitter who had a few balls bounce his way, and the Baseline attempts to correct for this.
\nSimilarly, a pitcher with an unusually low EqHR9 rate, but a high flyball rate, is likely to have achieved the low EqHR9 partly as a result of luck. In addition, the Baseline corrects for large disparities between a pitchers ERA and his PERA, and an unusually high or low hit rate on balls in play, which are highly subject to luck. ';
xxxpxxxxx1160184488_32 = 'Approximate number of batting outs made while playing this position.';
xxxpxxxxx1160184488_33 = 'Batting average; hits divided by at-bats. In PECOTA, Batting Average is one of five primary production metrics used in identifying a hitters comparables. It is defined as H/AB. ';
xxxpxxxxx1160184488_34 = 'Bases on Balls, or bases on balls allowed.';
xxxpxxxxx1160184488_35 = 'Bases on balls allowed per 9 innings pitched.';
xxxpxxxxx1160184488_36 = 'Batters faced pitching.';
xxxpxxxxx1160184488_37 = 'Balks. Not recorded 1876-1880.';
xxxpxxxxx1160184488_38 = 'Batting Runs Above Replacement. The number of runs better than a hitter with a .230 EQA and the same number of outs; EQR - 5 * OUT * .230^2.5.';
xxxpxxxxx1160184488_39 = 'Batting runs above a replacement at the same position. A replacement position player is one with an EQA equal to (230/260) times the average EqA for that position.';
xxxpxxxxx1160184488_40 = 'Breakout Rate is the percent chance that a hitters EqR/27 or a pitchers EqERA will improve by at least 20% relative to the weighted average of his EqR/27 in his three previous seasons of performance. High breakout rates are indicative of upside risk.
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